In modern projection objectives for microlithography, a multiplicity of wavefront manipulators are often used for correcting optical aberrations. Most of the manipulators can bring about a wavefront correction via mechanical manipulation of optical elements. This takes place either via position change and/or via a deformation of the optical elements. The manipulators often have correction properties for low-order wavefront aberrations such as typically occur when using the objectives in conjunction with so-called conventional settings and at a throughput of approximately 120 wafers/hour.